Value of changing fork oil/rebuilding forks. 2015. 17k miles

[BruinFJRguy]

Hey all. I've poked around and have found varying results, not entirely on point, so I'll post this.

I'm thinking of changing the fork oil, or perhaps doing a full fork rebuild on my 2015 with 17k miles. Is there value in this?

I've also thought about doing more work to the suspension (springs? valves?). For my purposes in the twisties, I find my settings on the suspension either soft but unstable or hard (better handling) but very jarring on my wrists. I weight about 170 lbs out of the shower. Add a bit to that with gear etc.

I'm open to any suggestions. I've read that the oil probably looks crappy. I've also read that the oil is probably very thin and it's dampening value is likely severely diminished. I've also read that all the crap in it thickens it up and makes dampening slower.

I realize the fork oil change is not that difficult. I did have my suspension out of whack for a few hundred miles, give or take, and had some serious pogo-ing going on. Maybe I should do my bushings and seals for kicks at this point, even though no oil is leaking.

Again, my goal is better handling in the twisties and an all around more pleasant ride. Thanks in advance!

[NTXFJR]

If you're doing this for performance in the twisties, you might consider a Racetec / Penske upgrade?

[fontanaman]

I have a 09 and change my fork oil annually. The fork bushings are coated with Teflon and it give up quickly with the debris finding it's way in to the oil. At 17k the bike does not need new bushings - it does need a fork oil change.

It is not likely replacing the fork oil will improve handling.

The stock 09 has awful (soft) suspension so I updated the front fork to GP Suspension and Penske in the rear. It handles great now but it is not a plush ride until I add some weight like a passenger or loaded for a trip - nice and smooth then.

The front forks are the same for an 09 and a 15 A model so consider a fork upgrade such as RaceTec or GP Suspension. Most say rear shock on the 15 is pretty good - beefed up over the 09.

[raYzerman]

I wouldn't do anything at 17k, go 30k. Bushings are OK, the oil mostly has aluminum oxide, which turns it gray, eventually some Teflon. Damping will change as you up the viscosity. Next time go a truer 5W or 7 or 7.5. To me the OEM damping is just fine, people do aftermarket springs and the damping valving at the same time, then rave. Mostly it was the spring change that made a huge difference, I'd do springs on prior to Gen3. The springs in your '15 are way better than Gen1/2, but are progressive. Crank the preload down further to reduce brake dive, it will compress the weaker part of the spring. Try 3 lines showing, maybe 2.
Set your damping at 8 clicks out, ride a loop of varied conditions, dial them in 4 clicks, ride the loop so you know what that feels like (likely too hard), back them out 2 clicks, ride the loop, now your closer. Tweak from there, tweak as you ride your real rides.
If you like spending money, get an aftermarket rear shock first, but yours is OK for your weight. No need for fork work.

PS - Jim, I get it on your annual oil change. Also Gen3 forks only have a damping cartridge on the right fork, none on the left. Any aftermarket valving can only be done on that side.

[FJRoss]

In around 185,000 miles, I have done fork seals and bushings twice - in both instances, the service was initiated by a fork oil leak that a SealMate wouldn't deal with. Fork oil a few times in between. The fork oil always comes out looking nasty and I typically replace it with Bel-Ray 5W. OEM cartridges but aftermarket (Hyperpro) springs. I notice (I think) some difference after changing the fork oil - not a huge change (at least to my perception). To be honest, I never really thought there was a very large handling change after doing the bushings despite the fact that a significant amount of the Teflon coating was worn away. Do others notice a large difference with new bushings??? (I'm not a ten tenths rider and I don't run it on a track.)

I think you would see more of an improvement by changing the fork innards (Traxxion etc.) For the Gen III "A" models, are people just doing the one fork (valve) and the springs in both? Or are they going to Gen II forks? In any case, I would change the oil (and maybe springs) and call it good until at least 30,000 miles and then consider the full meal deal if the spring change doesn't do it for you. I really don't think you will be terribly excited by the seals and bushing freshening.

[Hppants]

FWIW - I changed my fork oil ('14 A model) at about 30,000 miles and replaced the (filthy) stock oil with Honda Showa 5 wt. This resulted in a firmer ride (had to back off the pre-load 1/2 turn) and more compliant dampening. I didn't disassemble the forks (beyond loosening the cap) and used Kerosene as a solvent to loosen up and remove the gunk settled at the bottom. I did one final rinse with about 25 ml of fresh fork oil to remove the rest of the kerosene. Then after they drip dried, I filled the forks with the recommended volume using a graduated fork funnel I got from Cycle Gear.

I'm describing this to acknowledge that I cut a couple of corners, but (IMO) still got the desired results. I'm hoping this will extend the life of my bushings and seals, but only time will tell.

[fontanaman]

Thanks for setting me straight Ray. I forgot about the one legGed valve damper in the Gen III. Gen II suspenders suck but you have a Gen III so you are in a much better place. Most Gen III owners get by just fine with the stock suspension.

[raYzerman]

You may feel a slight difference and feel better with fresh oil, 17k I'd leave it. You won't feel any handling diff with new seals/bushings, but the new Teflon will slide with a tad less resistance. Remember the bottom bushing rides in a constant film of oil. Spending money on valving is a waste to me without trying new springs (Gen1/2) first. Some like straight rate springs, so you could swap out Gen3 for that (both sides as we always do). Jim, I find the one-legged damping is quite comparable to prior, I ride hard sometimes, I don't feel I need to swap it out. Had RaceTech, not a huge damping difference to me for the money spent. Hard core good twisty riders will want aftermarket valving and a rear shock.
Pants, next time don't worry about the volume, measure the level instead and never overfill.

[BruinFJRguy]

All sounds like good advice. I have next week freed up and am planning on taking off for a few days. I was trying to decide if it was worth tearing into the forks before leaving, using up some riding time. I think the answer is that any performance gains will be minimal, and I'm better off using the time to ride and swapping the fork oil after the trip.

I'm on the dials constantly and always have a hard time finding the sweet spot while riding in the twisties. I did have my preload almost all the way in for a while to decrease sag, but recently backed it out to about a line or so. Maybe I'll back it out a bit more and take your suggestions, raYzerman, and try retuning from scratch.

I'm probably over thinking all of this. Just want to get max value in the canyons.

[silverback]

It seems like there was a guy making a sh for the rear on Gen1 FJRs to up the spring preload and reduce sag. If I recall correctly, it was a ⅛" shim that fit under the spring. Compressing tgat spring may be hazardous and might be best left to a pro (or someone of your less favored political party).

I wanted to try this on my Gen2 but it left before I got a chance. The Gen 1 coukd have used all the help it could get, especially in the rear suspension.

Making a disk out of ⅛" plastic may well be cheaper than a full respring if you can find a good mechanic to compress the spring.

But...I am a cheap bastard and love to tinker with stuff.

[Uncle Hud]

I'm thinking of changing the fork oil, or perhaps doing a full fork rebuild on my 2015 with 17k miles. Is there value in this?

Hope not, since my 2015 has 61,000 miles on it and I ain't rebuilt shit. Of course, I ride like a grandpa.

[gixxerjasen]

Hmmmm

[raYzerman]

I'm on the dials constantly and always have a hard time finding the sweet spot while riding in the twisties. I did have my preload almost all the way in for a while to decrease sag, but recently backed it out to about a line or so. Maybe I'll back it out a bit more and take your suggestions, raYzerman, and try retuning from scratch.

Preload with progressive is a guess, at 1 line out not bad. Play less with the dials, it seems you don't know where you're at. You have to set it to something reasonable first, then should only tweak after that one click here or there. Twisty rider, rear shock 5 or 6 clicks out. Fork compression, 6-8 your preference, Rebound 7-8-9

[raYzerman]

I'm on the dials constantly and always have a hard time finding the sweet spot while riding in the twisties. I did have my preload almost all the way in for a while to decrease sag, but recently backed it out to about a line or so. Maybe I'll back it out a bit more and take your suggestions, raYzerman, and try retuning from scratch.

Preload with progressive is a guess, at 1 line out not bad. Play less with the dials, it seems you don't know where you're at. You have to set it to something reasonable first, then should only tweak after that one click here or there. Twisty rider, rear shock 5 or 6 clicks out. Fork compression, 6-8 your preference, Rebound 7-8-9. Tendency is to overdamp, right thing is least amount of damping that gets the job done.

[raYzerman]

I'm on the dials constantly and always have a hard time finding the sweet spot while riding in the twisties. I did have my preload almost all the way in for a while to decrease sag, but recently backed it out to about a line or so. Maybe I'll back it out a bit more and take your suggestions, raYzerman, and try retuning from scratch.

Preload with progressive is a guess, at 1 line out not bad. Play less with the dials, it seems you don't know where you're at. You have to set it to something reasonable first, then should only tweak after that one click here or there. Twisty rider, rear shock 5 or 6 clicks out. Fork compression, 6-7-8 your preference, Rebound 7-8-9. Tendency is to overdamp, right thing is least amount of damping that gets the job done.

[wheatonFJR]

Preload with progressive is a guess, at 1 line out not bad. Play less with the dials, it seems you don't know where you're at. You have to set it to something reasonable first, then should only tweak after that one click here or there. Twisty rider, rear shock 5 or 6 clicks out. Fork compression, 6-7-8 your preference, Rebound 7-8-9. Tendency is to overdamp, right thing is least amount of damping that gets the job done.

I'm on the dials constantly and always have a hard time finding the sweet spot while riding in the twisties. I did have my preload almost all the way in for a while to decrease sag, but recently backed it out to about a line or so. Maybe I'll back it out a bit more and take your suggestions, raYzerman, and try retuning from scratch.

Preload with progressive is a guess, at 1 line out not bad. Play less with the dials, it seems you don't know where you're at. You have to set it to something reasonable first, then should only tweak after that one click here or there. Twisty rider, rear shock 5 or 6 clicks out. Fork compression, 6-8 your preference, Rebound 7-8-9. Tendency is to overdamp, right thing is least amount of damping that gets the job done.

I'm on the dials constantly and always have a hard time finding the sweet spot while riding in the twisties. I did have my preload almost all the way in for a while to decrease sag, but recently backed it out to about a line or so. Maybe I'll back it out a bit more and take your suggestions, raYzerman, and try retuning from scratch.

Preload with progressive is a guess, at 1 line out not bad. Play less with the dials, it seems you don't know where you're at. You have to set it to something reasonable first, then should only tweak after that one click here or there. Twisty rider, rear shock 5 or 6 clicks out. Fork compression, 6-8 your preference, Rebound 7-8-9

Use the fricken edit button, whydoncha?

[raYzerman]

Did that, this is very strange.

[fontanaman]

Did that, this is very strange.

It's ok Ray after all this is the FJRiders forum. We live for strange.

[BruinFJRguy]

I usually do about 8 clicks out rebound, 9 out compression in twisties and 11 normal driving. About 9 out rebound in rear shock.

I think I'm in the zone, it's just not as compliant and smooth as I would like. Either bouncy or jarring. I think I've obsessed about it to death. If there's no "fix" I'm probably just getting all I can out of it already. I suppose it's not actually a race bike.

[BruinFJRguy]

My preference might be down to about 7 or 8 compression. I do think there's a chance the oil is doing just a little less dampening when hot.

Ahh well. I'll go for my next big ride and freshen up the oil when I get home and report back.